Adam Slapczynski

 I'm not sure if this is a relative or not. His DOB puts him as a contemporary of my Great-Grandpa - maybe a brother or cousin? (more likely the latter as he shares a name with my Great-Great Grandpa, and is six years junior to my Great-Grandpa). From the web: Adam Slapczynski was born in 1888. He studied mathematics at the University of St. Petersburg. After the outbreak of the revolution he returned with his family to Polish, he taught mathematics in secondary schools. In 1923. He was a teacher in the Gymnasium. John Śniadeckiego in Kielce. Already in 1939. Begins a secret teaching. He was arrested on July 9, 1941 r. After the auditions in Kielce prison, died in a railway carriage in a transport to Auschwitz on August 1, 1941.